How to be cool with a 5yr old boy?

Sounds like the problem is you, not the boy. The little boy is pretty smart and is picking up on your insecurity and it's creeping him out. Stop trying so hard and just try to work with him. It could very well be a clash of personalities. He could also just be very independent and sure of himself.

Think of it this way...what if a boy/man your age was interested in you and tried really hard to attract you and you just weren't interested but he kept trying? Wouldn't you feel creepy about it?

I don't know what your wardrobe looks like or if you wear make up but perhaps try a few simple things about yourself...dress up more...more colorful clothes, things that kids like (animals, alphabetical stuff & colors) stuff with pockets; style your hair differently; wear make up...simple stuff like that.

Also, consider asking the kid "How was your day?...What did you do today?...."

Best of luck.

lol, you are trying way to hard, just play with them and be goofy. kids love when an adult actually plays with them and talks to them. i love the things kids say and do, so just have fun and be a kid yourself (a responsible kid that is bc u are the adult) so have fun but be safe and reasonable at the same time bc kids need to know that you (the adult) is the one in charge

Stop being insecure. Just be yourself. Don't worry about other people.